PXW-Z150 low light issues - help? at DVinfo.net

Go Back   DV Info Net > Most Recent Additions... > Sony 4K Ultra HD Handhelds

Sony 4K Ultra HD Handhelds
Pro and consumer versions including PXW-Z150, PXW-Z100, PXW-X70 / FDR-AX100


Reply
 
Thread Tools Search this Thread
Old September 18th, 2016, 07:22 PM   #1
New Boot
 
Join Date: Sep 2013
Location: Melbourne, Australia
Posts: 14
PXW-Z150 low light issues - help?

I shoot primarily dance concerts (so indoor, stage lighting). I've been shooting with a Sony NX5 the past few years, which itself was an upgrade from a Sony Z1 (i.e. I've been shooting with this line of cameras for a while). I've just purchased a Sony PXW-Z150, and shot with it for the first time yesterday - the results were not what I expected.

I shot with the NX5, I set the Z150 up to record the same show in 4K as a wide shot for a test, to review what it looked like later. Here's a still from the NX5:
http://www.dvnonstop.com/pxw-z150/20...5.Still001.jpg

Obviously I was zoomed in on the NX5, here's the same frame extracted/cropped from the 4K recording:
http://www.dvnonstop.com/pxw-z150/Cl...ll001_Crop.jpg

Here's the original Z150 full frame wide shot for reference:
http://www.dvnonstop.com/pxw-z150/Cl...7.Still001.jpg

The NX5 was f3.7, no gain, shutter 50, focus 12m, white 4400K.
The Z150 was f2.8, 6db gain, shutter 50, focus 10m(?), white 4400K.

(The Z150 manual focus stops were 10m, and then 20m, nothing in between? The subjects in the shot are standing on marks at 12m, the stage was between 8m (front) and 17m (rear) from where I was).

I had read through various articles about the Z150 in low light, I was still surprised I needed any gain at all for stage lights. Looking at it now, I do think I had the gain a little high (I set the camera up before the show started, and couldn't adjust it during). Even so, there is a LOT of apparent noise to me in the Z150 image - which is historically what I would have expected on older cameras once you start ramping up the gain. But I've seen various examples on this forum from other Z150 shooters, without the same level of apparent noise. Please someone tell me I'm doing this wrong? I can see see there additional picture profile settings to the NX5, I'm hoping there's something in there I haven't learned yet that will help, but I'm still somewhat shocked that the Z150 apparently needs so much more light, compared to the much older NX5.
Peter Barton is offline   Reply With Quote
Old September 18th, 2016, 09:29 PM   #2
Inner Circle
 
Join Date: Mar 2003
Location: Ottawa, Ontario, Canada
Posts: 3,743
Re: PXW-Z150 low light issues - help?

A comparison for you of my cameras and a x70 I tried a while back. All set on automatic in my living room as a simple test. All images look to be about the same brightness. The 1" sensor looses some of its size advantage because of the lens. I did not get the X70 but got the AX100. The stacked sensor in the Z150 is supposed to be better but I am sure your tests are correct that it cannot compete with the NX5. I am sure the newer NX5R would be even better. In my tests even the older 1/3" NX30U was a little better in low light and I now have the AX53 which is a little better than the AX100. However the AX100 has the edge in picture quality and full manual control but not by much considering it is twice the cost.

NX5U F1.7 9db
X70 F2.8 24db
NX30U F2.0 18db
AX1 F1.7 24db

Ron Evans
Ron Evans is offline   Reply With Quote
Old September 18th, 2016, 11:53 PM   #3
New Boot
 
Join Date: Sep 2013
Location: Melbourne, Australia
Posts: 14
Re: PXW-Z150 low light issues - help?

Sounds like I have just made a (very expensive) mistake. How can the camera that is 5 years newer be so much poorer? I've seen footage on this forum shot with it (at night with lots of gain), that doesn't have the apparent grain mine did, so I'm still hoping I can improve this. I wouldn't have bought the camera to shoot anything dimly lit, but it seemed for stage lighting it should have been fine (I would have actually thought this a fairly standard scenario for this type of camera).

As far as I could see, the NX5 was obsolete, and the Z150 was the replacement unit in the range. I wasn't aware of the NX5R, and it looks like it isn't quite out yet. If I can't get the Z150 looking a bit closer to the NX5, I guess I'm stuck now trying to sell it second hand, and picking up an NX5R.
Peter Barton is offline   Reply With Quote
Old September 19th, 2016, 12:12 AM   #4
Trustee
 
Join Date: Jan 2013
Location: San Diego, Califonia
Posts: 1,113
Re: PXW-Z150 low light issues - help?

The problem is that they are shoving more pixels into the sensor because people want higher resolution, which means smaller pixels, and less area to collect light photons. Can you imagine what a 1080p only FF A7sII sensor would be capable of? :-)

I find I can shoot ENG comfortably up to 27db without even really noticing anything horrible. 30db and 3db in a pinch, although on the X70, 27db looks like 33db on the Z150. I shoot ENG all the time at maximum 33db gain on the Z150. My station issued JVC ProHD cameras look worse at 9db than the Sony does at 33db, and the JVC's can go all the way to 36db, or what I call "grey snow". :-\

Paul
Paul Anderegg is offline   Reply With Quote
Old September 19th, 2016, 12:16 AM   #5
Trustee
 
Join Date: Jan 2013
Location: San Diego, Califonia
Posts: 1,113
Re: PXW-Z150 low light issues - help?

BTW, convert that Z150 4K footage into 1080p 4:2:2 and then pixel-peep the noise again. :-)

Paul
Paul Anderegg is offline   Reply With Quote
Old September 19th, 2016, 02:14 AM   #6
New Boot
 
Join Date: Sep 2013
Location: Melbourne, Australia
Posts: 14
Re: PXW-Z150 low light issues - help?

Thanks Paul, I've seen some of your videos posted, and that's what surprised me most. You've identified the gain used on some of those, and I could not particularly make out any noise, from either the gain or the low light - so this was a bit of a shocker. I'm thinking now the gain might not fully be the issue, but also the sensor itself with large blocks of solid colour.

I've converted it down to 1080p, and some other tests, it looks "better", but still not as clean as the NX5 - it's still snowing purple in the background, just a bit less. And it seems a bit pointless to have bought a 4K camera if the footage isn't useable at that resolution.

Apart from the solid colours in the backdrop, the rest of the image is at least equivalent to the NX5. And the footage looks much nicer in progressive than interlaced. So it's not all negatives, in fact probably just the one negative, but it's unfortunately a pretty big one.

I'm in two minds what to do. If I zoom/follow with the Z150, I'll obviously get a better result than what I did just leaving it on a wide shot. But I'm not convinced at this point that it is going to match the NX5. And anything further I film will effectively be testing live on customer jobs. If I can't find any way to improve this, I'm seriously considering trying to return the camera if I can (probably will still cost me something, but hopefully not much), or otherwise trying to sell it. I don't think I can film my customer's jobs this year, and deliver them something that doesn't look as clean as what I shot for them on the older camera last year.
Peter Barton is offline   Reply With Quote
Old September 19th, 2016, 02:54 AM   #7
Trustee
 
Join Date: Jan 2013
Location: San Diego, Califonia
Posts: 1,113
Re: PXW-Z150 low light issues - help?

The 3MOS in the NX5 should have better color reproduction than the single sensor in the Z150. Also, I advise against shooting anything in 4K unless you have a need for that footage in 4K. I typically found that all of the 3MOS Sony's I tried, including the X180, had better image quality than the X70/Z150, but the X180 just did poorly at high gain, lots of smearing and noise reduction at play. You might also want to mess with the detail adjustments, as detail levels on UHD on the Z150 are VERY ENHANCED. I use 0 on 720 and 1080, but when I got my 4K TV, I could see it was very over-enhanced at 0 level in UHD mode.

I considering an NX5R to replace my Z150, but I would need to play with one first. It checks all the boxes for 720p60, built in live streaming, and SDI out, but you know how Sony hides demons in the details, like no EVF when live streaming, or the camera explodes if you attempt to output SDI while recording, that stuff. :-D

Paul
Paul Anderegg is offline   Reply With Quote
Old September 19th, 2016, 07:37 AM   #8
Inner Circle
 
Join Date: Mar 2003
Location: Ottawa, Ontario, Canada
Posts: 3,743
Re: PXW-Z150 low light issues - help?

If you are shooting dance at 50/60P on the NX5 then the 4K of the Z150 is only 25/30P. That is why I got a FDR-AX1 so that I could shoot at 60P UHD. I am sensitive to the slow frame rates so like 60P for all my cameras. I am looking at the Panasonic HC-X1 or AG-UX180 to replace my FDR-AX1 but will have to wait and see how they perform as they may have a Sony 1" sensor !!! My wife uses the AX100 for closeups and for that it works well. Things I liked on the Z150 was that it used the same batteries and Lanc controllers that I have a few of. But didn't like the fact that it was only 30P UHD, lacked touch LCD and all the nice touch functions of the AX100 or X70. We use touch focus on all the unattended cameras. Focus is super critical for UHD and if it is off it is very obvious. Most of the time I leave the FDR-AX1 when unattended in auto focus.

Ron Evans
Ron Evans is offline   Reply With Quote
Old September 19th, 2016, 10:34 AM   #9
Major Player
 
Join Date: Jun 2008
Location: Milwaukee WI
Posts: 573
Re: PXW-Z150 low light issues - help?

Perhaps the hideous neon pink is messing with the sensor?

Thanks

Jeff
Jeff Pulera is offline   Reply With Quote
Old September 19th, 2016, 12:16 PM   #10
Inner Circle
 
Join Date: Mar 2003
Location: Ottawa, Ontario, Canada
Posts: 3,743
Re: PXW-Z150 low light issues - help?

Both the AX100 and the AX53 overexpose easily ( typical Sony ) and I prefer to under expose a little and just raise a little in editing. I seem to always drop the chroma a little too so a combination of slight over expose and chroma too high with that pink may cause a lot of the problem. I set my unattended camera focus with spot focus and AE shift on - 0.7 most of the time.

Ron Evans
Ron Evans is offline   Reply With Quote
Old September 19th, 2016, 08:00 PM   #11
New Boot
 
Join Date: Sep 2013
Location: Melbourne, Australia
Posts: 14
Re: PXW-Z150 low light issues - help?

Jeff - the neon pink is certainly part of the problem, but that's not the only colour wash that had an issue. There's one item where the colour wash gets changed about every half second, a bunch of the colours come up fairly clean (not as solid as the NX5, but close enough), and a bunch of the colours come up with the same snow effect. I can post a clip online if anyone wants to take a look. Overall (for the whole concert) I would say it was about 50/50 between having a relatively clean image (almost as clean as the NX5), and having a snow effect going on.

Ron - mostly I shoot at 50i at this point, sometimes on multi-camera I have to match against a Z1 or Z7 shooting at 50i, and I also never sold myself on the resolution drop to go 720p. I was going to revisit that with some Z150 tests, but possibly not now (if it ends up going back!)
Peter Barton is offline   Reply With Quote
Old September 21st, 2016, 10:24 PM   #12
New Boot
 
Join Date: Sep 2013
Location: Melbourne, Australia
Posts: 14
Re: PXW-Z150 low light issues - help?

For anyone who is interested, Ive uploaded some video files of one of the items to Dropbox if you want to take a more detailed look:
https://www.dropbox.com/sh/h332vma5r...kLC3zspLa?dl=0

In this item from the concert, the colour wash changes throughout, which gives some additional insight into what the Z150 is doing. For some of the colour washes the Z150 is basically as clean as the NX5, but for all the purple/blue washes, the background becomes heavily corrupted.

NX5.mp4 is the item filmed from the NX5. Z150.mp4 is the wide shot from the Z150 in UHD. Z150 Zoom 1080.mp4 is the item from the Z150, but cropped to HD (1080) so basically youre just seeing the centre of the UHD image, which is a bit of a better comparison pixel for pixel to the NX5 footage. Not as perfect a comparison as if the Z150 had been zoomed, but the closest I can do from what was shot.

I'm currently in the process of returning the camera. Likely to cost me a hefty restocking fee (close to $1000), but it's not a camera I can otherwise use for what I'm doing, if this is how it performs.
Peter Barton is offline   Reply With Quote
Old September 22nd, 2016, 01:50 AM   #13
Trustee
 
Join Date: Jan 2013
Location: San Diego, Califonia
Posts: 1,113
Re: PXW-Z150 low light issues - help?

Peter, how would you compare the noise of the NX5 vs the Z150 at their maximum gain settings? Which is cleaner, and if the difference is substantial, please advise. Still thinking of picking up a NX5R.

Paul
Paul Anderegg is offline   Reply With Quote
Old September 22nd, 2016, 08:44 AM   #14
Inner Circle
 
Join Date: Mar 2003
Location: Ottawa, Ontario, Canada
Posts: 3,743
Re: PXW-Z150 low light issues - help?

It looks like the NX5R is an upgraded NX3 so comparisons there may be similar.

My NX5U is not a match for the clean image of any of my small Sony's though when gain is used. Above 12db the NX5U is just not usable even at 12db I use Neat to clean up image. I normally limit use to 9db. By contrast the AX53 or AX100 are good beyond 21db and shooting 60P have a noticeably sharper image than the NX5U too.

Ron Evans
Ron Evans is offline   Reply With Quote
Old September 22nd, 2016, 08:28 PM   #15
New Boot
 
Join Date: Sep 2013
Location: Melbourne, Australia
Posts: 14
Re: PXW-Z150 low light issues - help?

Paul, for output results with images of comparable luminance, the NX5 & Z150 are pretty comparable in my eyes. I would say there is slightly less noise in the Z150. It's difficult to get a true comparison, as the NX5 takes in so much more light to begin with, and doesn't need as much gain to get the same level of light in the final image.

Here's some quick tests for you:
http://www.dvnonstop.com/pxw-z150/Z150_f3-4_gain33.tif
http://www.dvnonstop.com/pxw-z150/NX5_f3-4_gain21.tif
http://www.dvnonstop.com/pxw-z150/NX5_f1-8_gain21.tif

First image is Z150, f3.4 (as open as it will go), gain 33 (max).
Second image is NX5, f3.4 (to match Z150), gain 21 (max).
Third image is NX5, f1.8 (as open as it will go), gain 21 (max).

Sorry about the NX5 white balance, I will try to re-do this. If you compare the first and third images, the NX5 brings it up slightly brighter to me, with comparable noise (NX5 is noisier, but probably doesn't need 21 gain to match the luminance of the Z150 image at 33 gain). It will be useful to see the NX5 image with proper white balance though!

Ron, thanks for the info, I will have to check out the NX3 specs. So long as they're a close match to the NX5, particularly the sensor, the new NX5 will hopefully be the camera for me. I basically never have to use gain in any of what I shoot with the NX5, there is always more than enough light for that camera in what I do.
Peter Barton is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

Omega Broadcast
(512) 251-7778
Austin, TX

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

EVS
(800) 238-8480
Glendale, CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Most Recent Additions... > Sony 4K Ultra HD Handhelds

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 07:46 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2015 The Digital Video Information Network